Jonathan Cowie took on a monumental task in writing Climate Change—a book that covers climate science and the interactions of climate with the biosphere and geosphere from the inception of life to modern times. Given the book's vast scope, it is not surprising that the level of detail, the completeness of information, and the quality of writing vary considerably. Initially, I was somewhat ambivalent, but as I got deeper into this tome, I became more and more impressed by just how well Cowie tied together so many disciplines—all of which are relevant if one wants more than a superficial understanding of what human greenhouse emissions mean for our planet.

There is so much to gain from Cowie's book that I can easily forgive its problems and limitations. Climate Change has flaws, and some chapters have an obvious European (particularly UK) bias, but those aspects should not deter readers. I know of no other source, including the Intergovernmental Panel on Climate Change (IPCC), that brings together the breadth and depth of material that this book does. There is sufficient repetition and cross-referencing so a reader may choose among topics and read only the ones of interest without losing a sense of completeness. This is one of the strongest points of the book. While I dutifully provide critique here, the bottom line is that anyone who wants to understand climate change and its impacts, but who doesn't have time to earn a PhD on the topic, should buy this book.

The title may be misinterpreted by people expecting a focus on modern-day species. While Cowie does a splendid job of summarizing modern-day impacts on wild species and on society, there is as much climate science, atmospheric science, oceanography, biochemistry, and biogeochemistry as there is organismal biology. Cowie does a brilliant job of weaving together the evolution of life with the evolution of Earth's climate. This topic occupies the first third of the book. Many of us know intellectually that the two are connected, but how many of us could explain the interconnections in any detail to another person, much less give a lecture on the topic? For those who would like to be able to do just that, Cowie provides the material.

As implied earlier, however, this is not a perfect work. The wording is rough in many sections, probably the result of a push to get the book published quickly. Speed is important, though, because the topic is timely and because the science is moving so rapidly that the content can quickly become outdated. I consider this an acceptable trade-off, given the very broad scope of the material Cowie covers. Further, the explicit aim of this book is to inform, not to serve as pleasurable bedtime reading.

Perhaps because of that haste, some sections are not clear. Unfortunately, a lack of critical information causes misrepresentation of the data in a few instances, the worst case of which concerns Cowie's treatment of the Holocene (chapters 4 and 5). He writes extensively about recent (Holocene) climate in relation to 20th-century climate, beautifully detailing extreme cold/warm and wet/dry periods in terms of temperatures, ice extent, and species' distributions. However, these trends are all derived from Northern Hemisphere data (principally from Europe, with some from Eurasia and even less from North America). The trends are far from consistent spatially, especially between the Northern and Southern Hemispheres. Although records are patchy, what evidence there is indicates that short-term climate extremes, such as the Medieval Warm Period and the Little Ice Age, were regional in nature, and that climatic fluctuations during the past 11,000 years tended to be asynchronous on a global scale. Thus, the general agreement among climate scientists is that in spite of some strong regional trends, global temperatures over the past 10,000 years are unlikely to have ever exceeded late 20th-century warming. This is an extremely important point when attempting to estimate the impacts of recent and near-future warming, and one that Cowie fails to identify in this discussion.

I was also disappointed with Cowie's treatment of recent and projected impacts for the United States. Cowie relied heavily on the US climate assessment produced by the US Global Change Research Program in 2000 rather than on more up-to-date primary literature. Not only was the US climate assessment weak on observed and projected impacts in natural systems, but its climate projections were quickly superceded, and for many regions, newer model projections conflict with the older ones used in the 2000 assessment. There were also some minor inaccuracies in descriptions and citations for some specific examples; these are not important to the overall messages, but they may matter to some readers.

Although I still recommend this book overall, if there is some particular information that is vital to the reader, it would be advisable to investigate key details by delving into the original studies. Fortunately, Cowie supplies ample references so that the reader can do just that. Indeed, part of the value of this book is as an inroad into the primary literature for each of the topics covered.

In contrast to the section covering the United States, other sections are absolutely brilliant. The second third of the book focuses broadly on climate during human and societal evolution. I was particularly impressed by Cowie's discussion of the impacts that relatively small levels of climate change can have on society. His depictions of the famines and diseases that devastated Europe and China as these regions moved out of the Medieval Warm Period and into the Little Ice Age are as fascinating as they are horrifying. Cowie points out that these episodes demonstrate how vulnerable society is to relatively small changes in regional climate. With less genetic diversity in existence in modern agriculture than there was in medieval agriculture, society may be even more vulnerable now.

The last third of the book focuses directly on the human dimensions of climate change, including technological approaches to mitigation, energy policy and alternative energies, food production, sustainability, and human health. These topics are covered in enough detail to provide a well-rounded base of knowledge, and as with the earlier sections, references give the reader the option of learning more.

Cowie makes a bold transition from the earlier part of the book, which focuses on natural science, to the latter part, which focuses on society. He starts the societal discussion with a blunt yet thoughtful appraisal of the pivotal role that the sheer number of humans plays in producing climate change in the first place and in affecting our ability to both mitigate and adapt to future impacts. This is very much a late-night topic among conservation biologists and ecologists, but it is rarely brought to the forefront in public discourse on sustainability in general and on climate change in particular. Lowering the global population growth rate is perhaps the single most important action we could take to alleviate environmental degradation of many kinds and to promote a better quality of life and human well-being. I doubt it's coincidental that the IPCC emission scenario that results in the lowest average global warming (the B1 scenario) assumes not only the use of “green” energy but also a decline in the global population after 2050.

The failure of human population issues to rise to prominence in policy discussions is a result of political unviability, not scientific unimportance. Cowie himself puts it well: “If we are to comprehend and address climate change concerns and the implications for species, including our own, then this understanding needs to come from science.... If we fail...well, someone else can narrate doom and disaster, at least as far as human and many wildlife species are concerned. As for the rest of the biosphere, it will go on.”